WO1990013680A1 - Procede pour produire conjointement des chlorures de metal et du tetrachlorure de titane - Google Patents

Procede pour produire conjointement des chlorures de metal et du tetrachlorure de titane Download PDF

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Publication number
WO1990013680A1
WO1990013680A1 PCT/US1990/002107 US9002107W WO9013680A1 WO 1990013680 A1 WO1990013680 A1 WO 1990013680A1 US 9002107 W US9002107 W US 9002107W WO 9013680 A1 WO9013680 A1 WO 9013680A1
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WO
WIPO (PCT)
Prior art keywords
metal
mixture
titanium dioxide
reactive mixture
metal component
Prior art date
Application number
PCT/US1990/002107
Other languages
English (en)
Inventor
Kenneth J. Richards
Theodore A. Rado
Original Assignee
Kerr-Mcgee Chemical Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kerr-Mcgee Chemical Corporation filed Critical Kerr-Mcgee Chemical Corporation
Publication of WO1990013680A1 publication Critical patent/WO1990013680A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G1/00—Methods of preparing compounds of metals not covered by subclasses C01B, C01C, C01D, or C01F, in general
    • C01G1/06—Halides
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B34/00—Obtaining refractory metals
    • C22B34/10—Obtaining titanium, zirconium or hafnium
    • C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08
    • C22B34/1218—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by dry processes
    • C22B34/1231—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by dry processes treatment or purification of titanium containing products obtained by dry processes, e.g. condensation

Definitions

  • the invention relates to the production of volatile metal chlorides and more particularly to the production of volatile metal chlorides jointly with titanium tetra- chloride.
  • Volatile metal chlorides and methods for their manufacture are known.
  • the simplest, most widely employed method is the direct chlorination of the metals themselves.
  • tin tetrachlor ⁇ ide which is a liquid at room temperature and atmos ⁇ pheric pressure, is prepared commercially either by direct chlorination of tin metal in a molten state or of finely divided tin metal suspended in a suitable medium such as tin tetrachloride.
  • the quantities of volatile metal chlorides produced annually are rela- tively small. This particularly is true when compared to, for instance, the quantities of titanium tetrachlor ⁇ ide manufactured each year.
  • the production of such relatively small quantities is necessitated by the limited demand and uses for these volatile metal chlor- ides.
  • Unfortunately it is the production of such small scale quantities which results in the high unit production costs for these materials.
  • a process whereby these volatile metal chlorides could be produced in such relatively small quantities but at lower unit production costs, such as those associated with the large scale manufacture of titanium tetrachloride, would offer a significant economic advantage.
  • the process constituting the present invention offers such an advantage.
  • a reactive mixture comprised of a metal component-contain- ing material, a titanium dioxide-containing material and a carbonaceous reducing agent first is formed in a suit ⁇ able chlorination zone.
  • This mixture is reacted within the chlorination zone by contacting the mixture with a chlorinating agent at an elevated temperature sufficient to effect reduction and chlorination of the metal com ⁇ ponent containing material and titanium dioxide-contain ⁇ ing material and produce a vaporous product mixture of volatilized metal chloride and titanium tetrachloride reaction products.
  • the vaporous product mixture is recovered from the chlorination zone and subjected to condensation under conditions whereby at least one of the metal chloride and the titanium tetrachloride reaction products con ⁇ tained therein is condensed. Following the condensation of the vaporous product mixture, the condensed metal chloride, titanium tetrachloride, or both are recovered therefrom.
  • the process constituting the present invention broadly is applicable to the production of any metal chloride from a metal component-containing material and which metal chloride is volatile at the operating temperatures utilized in the process and particularly at the temperatures employed in the hereinafter described chlorination step of the process.
  • the metal chlorides which can be produced by the process of this invention generally can be any metal chloride which possesses a vapor pressure, at the chlor ⁇ ination temperatures employed, of at least about 20 mm Hg.
  • the process of the present invention is particularly applicable to the production of the various chlorides of the metals of Groups lb, lib. Ilia, IVa, Va, Via and VIII of the
  • the chlorides of the metals of these Groups all possess vapor pressures considerably in excess of the above specified minimum vapor pressure at the chlorination temperatures employed and thus, all are readily recoverable from a chlorina ⁇ tion zone and can be produced in economically practical quantities.
  • Representative, but nonlimiting examples, of the metals within these Groups are, for instance, copper, zinc, cadmium, boron, aluminum, gallium, indium, silicon, germanium, tin, lead, arsenic, antimony, bis ⁇ muth, iron, selenium and the like.
  • the chlor ⁇ ides of these metals may themselves be either solids or liquids at room temperature and atmospheric pres- sure, they all are essentially completely volatile at the chlorination temperatures hereinafter disclosed, thereby rendering them readily recoverable.
  • a more preferred application of the process of this invention is in the preparation of the various chlorides of the metals of Groups IVa and Va of the Periodic Table of Elements. These groups include, for instance, such metals as germanium, tin, silicon, antimony and arsenic.
  • the use of the process of this invention to produce the chlorides of these metals is most advantageous since such chlorides are readily volatilized and many are liquids at room temperature and atmospheric pressure. Thus, not only can these materials be economically pro ⁇ prised utilizing the process described herein, but many also can be easily separated from the coproduced titanium tetrachloride and purified using simple frac- tionation techniques well-known to those of ordinary skill in this art.
  • the present invention broadly is applicable to the preparation of any volatile metal chloride from any metal component-containing material.
  • metal component-containing materials means any ore, ore concentrate or other material derived therefrom in which the metal component can be present therein in the form of the free or elemental metal or is chemically bound to a nonmetallic moiety including, but by no means limited to, oxygen, sulfur, carbon and the like, and mixtures thereof.
  • the metal components contained in the metal component-containing material can comprise the free or elemental metal itself or the oxides, sulfides and carbides thereof.
  • the preparation of the volatile metal chlorides is carried out jointly with the preparation of titanium tetrachloride using any of the static or fluidized bed or molten salt bath chlorination techniques known in this technical field.
  • the process is described below particularly with regard to the preparation of tin tetrachloride (a volatile, metal chloride which is liquid at room tem ⁇ perature and atmospheric pressure) jointly with titanium tetrachloride employing fluidized bed chlorination techniques.
  • a titanium dioxide-containing material, a tin dioxide-containing material (i.e., the metal component-containing material) and a carbonaceous reducing agent individually are introduced, via inlet conduits 10, 12 and 14 respec ⁇ tively, into .a chlorination zone 18 to provide therein a reactive mixture.
  • a titanium dioxide- and tin dioxide-containing materials and the carbonaceous redu- cing agent will be introduced into the chlorination zone 18 in the form of particulate solids and be of a size capable of ready fluidization.
  • the size of the par ⁇ ticulate titanium dioxide- and tin dioxide-containing materials contained therein will range from about minus
  • the sources of the titanium dioxide- and tin dioxide-containing materials employed to provide the readily fluidizable reactive mixture within the chlor ⁇ ination zone 18 are not critical.
  • the titanium dioxide- and tin dioxide-containing materials which can be used in the practice of this invention can include any of the known materials containing these particular metal oxide constituents.
  • Representative, but nonlimiting, examples of useful titanium dioxide- containing materials include, for instance, rutile, ilmenite and Brookite ores and the like, titanium dioxide enriched ore concentrates resulting from the beneficiation of any of the above disclosed ores and titanium dioxide-rich slags such as, for instance, slags produced by the electrosmelting of the naturally occurring ores or ore concentrates.
  • tin dioxide-containing materials include cassiterite ore and other tin dioxide-containing ores found in low grade alluvial or eluvial placer deposits as well as ore concentrates thereof.
  • concentration of the titanium dioxide and tin dioxide present in the particular materials being employed can vary widely depending upon the nature of these materials.
  • concentration of the titanium dioxide present in such materials can range broadly from about 50 to about 95 weight percent based upon the total weight of the material utilized depending upon whether this material is an ore, ore concentrate, or slag.
  • upgraded titanium dioxide-containing materials i.e., ore concentrates
  • synthetic rutiles prepared, for instance, by the acid leaching of ilmenite.
  • the titanium dioxide concen ⁇ tration in these synthetic rutiles typically can range from about 90 to about 95 weight percent or higher.
  • tin dioxide-containing materials such as the cassiterite ores
  • the tin dioxide concen ⁇ tration present therein also can vary widely.
  • the tin dioxide concentration of cassiterite ores can range from about 10 to about 100 weight percent based upon the total weight of the ore.
  • the metal component contained in the metal component- containing material is a metal sulfide it usually will be preferred to first convert the metal sulfide to the corresponding metal oxide. This readily can be accom ⁇ plished by methods known to those skilled in this art such as, for example, by roasting the metal sulfide- containing ore or ore concentrate under oxidizing conditions.
  • the particu- late titanium dioxide- and tin dioxide-containing materials will be introduced into the chlorination zone 18 in quantities sufficient to provide, within the reactive mixture, a weight ratio of the titanium dioxide to the tin dioxide of at least about 1:1 and preferably at least about 2:1. Most usually the quantities of the titanium dioxide- and tin dioxide-containing ores or ore concentrates or other metal component-containing mater- ials will be amounts sufficient to provide weight ratios of the titanium dioxide to the tin dioxide or other metal component-containing material ranging from about
  • the exact type and composition of the carbonaceous reducing agent introduced via an inlet conduit 14 into the chlorination zone 18 also generally will not be critical. However, this reducing agent preferably should be low in ash and free of hydrogen since the presence of the latter readily can lead to the produc- tion of hydrogen chloride.
  • calcined petroleum coke generally is the carbonaceous reducing agent of choice since it is both substantially free of ash and hydrogen.
  • the carbonaceous reducing agent will be in the form of particulate solids ranging from about minus 10 to about plus 150 mesh in size and will be added to the reactive mixture in at least a stoichiometric amount based upon the equivalents of the titanium dioxide and tin dioxide present therein.
  • a chlorinating agent is introduced via an inlet conduit 16 into the chlorination zone 18.
  • the rate of flow of the chlorinating agent through the inlet conduit 16 and into the chlorination zone 18 will be such, generally, to provide fluidization of the bed of the reactive mixture without excessive blowover of the bed from the chlorination zone 18.
  • the extent of blow- over of the bed generally will depend on such factors as the depth of the bed and the density and other physical characteristics (including the particle size) of the particulate titanium dioxide- and tin dioxide-containing materials and the carbonaceous reducing agent present in the bed.
  • the chlorination of the titanium dioxide- and tin dioxide-containing materials within the fluidized reactive mixture can be accomplished by any suitable chlorinating agent such as, for example, chlorine or a source of chlorine.
  • the chlor ⁇ inating agent of choice is anhydrous chlorine gas.
  • the chlorinating agent can be introduced into the chlorina ⁇ tion zone 18 at ambient temperatures or at elevated temperatures although ambient temperatures typically are employed.
  • the temperature of the fluidized reactive mixture of titanium dioxide and tin dioxide-containing materials and carbonaceous reduc ⁇ ing agent will be maintained at a temperature of at least about 600 * C and above.
  • the chlorina ⁇ tion temperatures will range from about 800 ⁇ C to about 1200 ⁇ C. At these temperatures the reduction/chlorina ⁇ tion reaction is self-sustaining.
  • the chlorina- tion zone 18 containing this reactive mixture is brought up to the above disclosed operating temperatures utili ⁇ zing known techniques.
  • one such technique includes igniting and burning any convenient solid fuel within the chlorination zone 18 until the desired operating temperature is obtained.
  • air can be introduced through the bottom of the chlorination zone 18 (by means not shown) to fluidize the reactive mixture contained therein.
  • the chlorinating agent e.g., chlorine gas
  • the chlorinating agent e.g., chlorine gas
  • the titanium dioxide- and tin dioxide-containing materials within the fluidized reactive mixture undergo reduction and chlor ⁇ ination to form a vaporous product mixture containing volatilized titanium and tin tetrachloride products.
  • This vaporous mixture may also contain other volatilized metal halides which may be formed from other metal components present as incidental impurities in the original titanium dioxide- and tin dioxide-containing materials.
  • the vaporous product mixture containing the volatilized titanium and tin tetrachlorides and any other volatilized metal halides present as impurities therein, together with any gaseous components such as carbon monoxide and carbon dioxide formed during the chlorination, is removed from the chlorination zone 18 by way of an outlet conduit 20.
  • the vaporous product mixture removed from the chlorination zone 18 also may contain entrained particulate solid materials such as, for instance, a portion of the carbonaceous reducing agent, a portion of the residues remaining from the chlorination of the titanium dioxide- and tin dioxide-containing materials and the like.
  • entrained particulate solid materials such as, for instance, a portion of the carbonaceous reducing agent, a portion of the residues remaining from the chlorination of the titanium dioxide- and tin dioxide-containing materials and the like.
  • the entrained particulate solid materials are separated from the vaporous product mixture, settled into a lower section of the gas/solids separation zone 22 and are removed therefrom via a solids outlet conduit 24.
  • the vaporous product mixture now substantially free of the entrained particulate solid materials, is removed from an upper section of the gas/solids separa ⁇ tion zone 22 via a vapor outlet conduit 26.
  • the vapor- ous product mixture removed from the upper section of the gas/solids separation zone 22 is conveyed through the conduit 26 to a condensation zone 28 wherein the vaporous mixture is condensed by means of either direct or indirect heat exchange.
  • the condensation of the vaporous product mixture can be effected through the use of indirect heat exchange employing a suitable cooling medium.
  • Typical of indirect heat exchange apparatus for use in the condensation zone 28 are, for example, conventional shell-and-tube type heat exchangers as well as plate type heat exchangers.
  • Suitable cooling medium for use in such heat exchangers can include, for instance, water or various process streams such as the liquid titanium tetrachloride and tin tetrachloride products produced in the process.
  • the temperature of the cooling medium will be such as to provide for cooling and thereby a conden ⁇ sation of the condensable constituents in the vaporous product mixture, i.e., the titanium tetrachloride and tin tetrachloride chlorination products.
  • the temperature of the cooling medium will be a temperature which, upon indirect heat exchange with the vaporous product mixture, is sufficient to cool the vaporous product mixture to a temperature below about the dew point temperature of at least the volatilized titanium tetrachloride and tin tetrachloride contained therein.
  • the titanium and tin tetrachlorides will be condensed and will collect in a lower section of the condensation zone 28 as a liquid product mixture.
  • Any noncondensable con ⁇ stituents such as, for example, carbon monoxide and carbon dioxide, will be collected in an upper section of the condensation zone 28 and will be removed therefrom via a conduit 30.
  • the condensed liquid product mixture which prin ⁇ cipally is comprised of liquid titanium tetrachloride and liquid tin tetrachloride, is removed from the lower section of the condensation zone 28 by way of an outlet conduit 32 and conveyed through the conduit 32 to a fractionation zone 34.
  • the fractionation zone 34 typi ⁇ cally can be a distillation column or tower such as, for instance, conventional packed or plate type towers. In general, the fractionation zone 34 will be maintained at a temperature sufficient to effect a fractionation of the liquid product mixture through revolatilization of the lowest boiling point metal chloride constituent present in this mixture.
  • the fractionation zone 34 will be operated at a temperature above about 11 ⁇ C, the boiling point of the tin tetra ⁇ chloride, and below about 136°C, the boiling point of the titanium tetrachloride. It is, of course, apparent to one of skill in this field that the precise tempera ⁇ ture or range of temperatures which can be utilized for carrying out the fractionation of liquid product mix ⁇ tures will vary depending upon the particular liquid metal chloride being co-produced together with the titanium tetrachloride.
  • a vaporous stream containing the revolatilized tin tetrachloride and any other volatilizable metal chlor ⁇ ides which may be present in the liquid reaction mixture and which have boiling points lower than that of titan ⁇ ium tetrachloride is removed from the fractionation zone 34 via a conduit 38 while a liquid effluent stream com ⁇ prised of the condensed titanium tetrachloride and any other nonvolatilized metal chlorides present having boiling points higher than that of titanium tetrachlor ⁇ ide, is removed from the fractionation zone 34 via a conduit 36.
  • the vaporous stream removed from the frac ⁇ tionation zone 34 via conduit 38 then is recondensed and subjected to purification (by means not shown) to reco- ver the tin tetrachloride contained therein as one principal product of the process.
  • the liquid effluent stream, containing the titanium tetrachloride and any other nonvolatilized metal chlorides, also is subjected to further purification (by means not shown) and finally recovered as another principal product of the process.
  • the process of this invention has been described above particularly with respect to the production of tin tetrachloride. As is known to those skilled in this art, this particular metal chloride is volatile at the elevated temperatures employed in the chlorination step and also is a liquid at room temperature and atmospheric pressure.
  • the process of this invention also is applicable to the production of various other metal chlorides which, although volatile at the chlorination temperatures employed, can be solids at room temperature and atmospheric pressure.
  • the metal chlorides can form particulate solids at temperatures significantly higher than the dew point (or condensation) temperature of the titanium tetra- chloride being co-produced therewith permitting the condensation, precipitation and separation of such volatilized metal chlorides from the remainder of the vaporous product mixture to be carried out simultane ⁇ ously.
  • the simultaneous condensation, precipitation and separation of such volatilized, metal chlorides can be effected in the gas/solids separation zone 22 and the separated solid metal chloride recovered therefrom via the solids outlet conduit 24.
  • the condensation and precipitation of the metal chloride into a particulate solid can be carried out by cooling of the vaporous product mixture either through the natural heat losses which occur within the conduit 20 or by spraying a liquid coolant such as liquid titanium tetrachloride into the vaporous product mixture.
  • liquid titanium tetrachloride can be sprayed into the conduit 26 (by means not shown) to condense and precipitate, as a particulate solid, the volatilized metal chloride contained in the vaporous product mixture and the solid metal chloride separated therefrom in an additional gas/solids separation zone (not shown) installed in the conduit 26.
  • the remainder of the vaporous product stream, comprising principally the volatilized titanium tetrachloride then will be removed from this additional gas/solids separation zone (not shown) and will be continued to be treated in accordance with the process of this invention.

Abstract

Est présenté un procédé pour produire des chlorures volatils de métal en même temps que du tétrachlorure de titane. Le procédé comprend la chloration d'un mélange réactif de susbtances contenant un composant métallique et du dioxyde de titane dans des conditions de réduction pour produire un mélange de produits à l'état de vapeur contenant du chlorure de métal rendu volatil et des produits de réaction du tétrachlorure de titane. Le mélange de produits à l'état de vapeur est ensuite soumis à condensation pour condenser au moins un des produits de réaction qu'il contient, à savoir le chlorure de métal rendu volatil ou le tétrachlorure de titane. Le mélange condensé est ensuite séparé pour en extraire au moins un produit de réaction condensé.
PCT/US1990/002107 1989-05-12 1990-04-20 Procede pour produire conjointement des chlorures de metal et du tetrachlorure de titane WO1990013680A1 (fr)

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US35104889A 1989-05-12 1989-05-12
US351,048 1989-05-12

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107164785A (zh) * 2017-05-24 2017-09-15 江西理工大学 一种铜电解液沉淀脱杂及沉淀剂氯化再生的方法
CN108910928A (zh) * 2018-09-18 2018-11-30 新特能源股份有限公司 两种金属氯化物的联产方法及两种金属氯化物

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2401544A (en) * 1943-06-24 1946-06-04 Stauffer Chemical Co Production of silicon tetrachloride and titanium tetrachloride
US2592021A (en) * 1947-07-26 1952-04-08 Schweizerhall Saeurefab Method for purifying normally liquid chlorides of metals of group 4 of the periodic system
US3156630A (en) * 1960-12-19 1964-11-10 Nat Distillers Chem Corp Purification of titanium tetrachloride by distillation in the presence of an oil and the use of an inert gas purge
US3156527A (en) * 1958-08-07 1964-11-10 British Titan Products Method for the production of titanium tetrachloride and zirconium chlorides
US3495936A (en) * 1967-06-08 1970-02-17 Du Pont Dilute phase chlorination of titaniferous ores

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2401544A (en) * 1943-06-24 1946-06-04 Stauffer Chemical Co Production of silicon tetrachloride and titanium tetrachloride
US2592021A (en) * 1947-07-26 1952-04-08 Schweizerhall Saeurefab Method for purifying normally liquid chlorides of metals of group 4 of the periodic system
US3156527A (en) * 1958-08-07 1964-11-10 British Titan Products Method for the production of titanium tetrachloride and zirconium chlorides
US3156630A (en) * 1960-12-19 1964-11-10 Nat Distillers Chem Corp Purification of titanium tetrachloride by distillation in the presence of an oil and the use of an inert gas purge
US3495936A (en) * 1967-06-08 1970-02-17 Du Pont Dilute phase chlorination of titaniferous ores

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107164785A (zh) * 2017-05-24 2017-09-15 江西理工大学 一种铜电解液沉淀脱杂及沉淀剂氯化再生的方法
CN108910928A (zh) * 2018-09-18 2018-11-30 新特能源股份有限公司 两种金属氯化物的联产方法及两种金属氯化物

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